Characterisation of the steel concrete interface submitted to chloride‐induced‐corrosion

Abstract This paper deals with the characterisation by means of electrochemical, gravimetric and analytical methods of chloride‐induced‐corrosion behaviour of steel coupons embedded in chloride‐containing‐cement pastes. Corrosion rates were estimated from electrochemical measurements as well as gravimetric ones. They vary from 2.6 to 5.7 µm/year for 5 and 10 g/L chloride‐containing‐cement pastes. Analytical characterisations (including optical and electronical microscopy and Raman micro‐spectroscopy) showed that corrosion patterns are not depending on the chloride content of the cement paste (5 and 10 g/L chloride in the interstitial solution). A localised corrosion pattern composed of pits growing inside the metallic substratum, a corrosion products layer (CPL) and a transformed medium (TM) was pointed out. CPL can be divided into two sub‐layers (CPL1 and CPL2), characterised by the presence or absence of calcium coming from the cement matrix.